z/VM: CP Commands and Utilities Reference - z/VM - IBM

SET THROTTLE
Usage Notes
Responses
Messages
1. CP can throttle devices that are eligible for I/O assist, but not while the device is
in I/O assist. When a device is in I/O assist, the guest is controlling the device
directly, not CP. CP can only throttle a device when it controls the I/O to and
from that device. Thus, if you throttle a device that is currently in I/O assist, CP
accepts your command, but does not actually begin throttling the device until
the device is no longer in I/O assist.
2. To display which devices are on the I/O throttling list and what their rates are,
use the QUERY THROTTLE command (page 1030).
3. You can also add devices to the I/O throttling list using the THROTTLE
statement in the system configuration file. For more information about the
THROTTLE statement, see the z/VM: CP Planning and Administration book.
Response 1:
To begin throttling a range of devices, enter the following:
set throttle 800-804 rate 10000
23:08:36 HCPTHR040E Device 0801 does not exist
23:08:36 HCPTHR040E Device 0804 does not exist
23:08:36 3 device(s) added to I/O throttling list starting with device 0800
23:08:36 2 device(s) skipped. Rate is 10000 I/Os per second
Response 2:
To stop throttling all devices, enter the following:
set throttle all off
23:09:32 The I/O throttling list has been cleared
Response 3:
To stop throttling a range of devices, enter the following:
set throttle 800-804 off
23:10:36 HCPTHR040E Device 0801 does not exist
23:10:36 HCPTHR040E Device 0804 does not exist
23:10:36 3 device(s) deleted from the I/O throttling list starting
with device 0800
23:10:36 2 device(s) skipped
Response 4:
To begin throttling a device, enter the following:
set throttle 800 rate 10000
23:25:24 Device 0800 added to I/O throttling list. Rate 10000 I/Os
per second
Response 5:
To stop throttling a device, enter the following:
set throttle 800 off
23:25:36 Device 0800 deleted from the I/O throttling list
HCP002E Invalid operand - operand HCP040E Device rdev does not exist
1404 z/VM: CP Commands and Utilities Reference